1. Field of the Invention
This invention relates generally to methods and apparatus used to detect of an object, item or person on a platform or elevated walkway.
2. Description of Related Prior Art
U.S. Pat. No. 7,380,375 discloses an alarm system for a loading dock. The alarm or safety system for a truck doorway such as a loading dock with an elevated platform provides an alarm that warns of a falling hazard that may exist due to the dock door being open while a truck is not present at the dock. In cases where a dock's open doorway is protected by a barrier that can be opened or closed, the alarm can be de-activated by closing the barrier. In some embodiments, the safety system includes a remote body sensor that detects when someone or something is near the doorway. In response to the body sensor, a second, more pronounced alarm can warn of more imminent danger where someone on the platform may be too close to an open doorway when a truck is not present.